Human error is my prime motivator pushing for automation, mostly because I'm the one getting fucked by it more often than not. I'm the guy processing data people enter or produce into automatic reports.

Every type of error I run into takes time to investigate, figure out how common it is and decide how to handle it. More often than not, I need to specifically document that handling too, because someone is gonna come asking for it.

"Your report says we had 17 invoices for Dec 2020, but we've booked 18" Yeah, because someone entered the booking month as 20212 or 200212 instead of 202012 and there's no reasonable way to parse that.
Nevermind the ones where the booking month is just "02". Like hell am I gonna write logic to guess the year if it's ambiguous.

Please just implement an automatic process to sync booking and invoicing systems. I don't have any magic tools to turn your slag into gold.